It is common for airbags to be used as an augmentation to seatbelt-provided protection in motor vehicles. FIG. 1 shows a simplified side view of a prior-art airbag deployment apparatus 18. Within a motor vehicle 22, a plurality of collision sensors (not shown) is electrically coupled to a vehicular computer 24. Vehicular computer 24 is electrically connected to a deployment activator 26 attached to an airbag 28.
In the event of a collision, one or more of the collision sensors sends a collision-detected signal (not shown) to vehicular computer 24. Vehicular computer 24 then sends a deployment-request RD to deployment activator 26. Deployment activator 26 typically contains a charge, which ignites and releases gasses upon receipt of deployment-request RD. The release of these gasses deploys airbag 28.
Airbag 28 is contoured to help restrain and to cushion an average adult human passenger when deployed. Desirably, the passenger is also restrained by a seatbelt 32 (shown in an unused position). The total restraint and cushioning provided serves to protect the passenger from excessive injury.
Potential problems exist when a seat 30 is a front passenger seat and the passenger is not an adult human being.
The “passenger” may be an inanimate object. Airbag 28 is contoured to restrain and cushion an adult human being. Therefore, depending upon the shape and size of the inanimate object, deploying airbag 28 may actually push the inanimate object into the adjacent driver's seat, thereby further endangering a driver above and beyond the danger presented by the collision. This is especially problematical when the inanimate object is not further restrained in the front passenger seat 30 by seatbelt 32.
An especially serious problem exists when the passenger is a child. In this case, deployment of airbag 28 places the child at severe risk of injury or death above and beyond those risks resulting from the collision. That is, deployment of airbag 28 may in and of itself place a child at risk of injury or death. This is especially true when the child is not further restrained by seatbelt 32.
Placing a child in a child carrier does not eliminate the risk of injury or death from the deployment of airbag 28. Indeed, when the passenger is an infant in a rearward-facing child carrier, the risk of injury or death due to the deployment of airbag 28 is greater than the risk of injury or death to a restrained older child in a forward-facing carrier.
In an ideal world, these dangers would not exist, as children and inanimate objects would not be located on front passenger seat 30. Rather, they would be secured in a rear seat where the risk of injury or death is significantly reduced.
In the real world, however, children and/or inanimate objects are often placed on front passenger seat 30, and are often unrestrained by seatbelt 32. Therefore, it is desirable that the deployment of airbag 28 be controlled to minimize the risk of injury or death due to that deployment. To this end, a plurality of prior-art apparatuses and methods of deployment (i.e., airbag deployment systems) have been invented.
A majority of these airbag deployment systems either replace, or require significant modification of, the factory-installed system of a motor vehicle 22. This increases significantly the cost of the system. At the same time, replacing or significantly modifying the factory-installed system adds a layer of complexity, which may increase the likelihood of system failure. For example, the failure of a single connection in an overly complex system may result in a failure of airbag 28 to deploy in the event of a collision when the passenger is an adult human. Worse, a single faulty connection may produce a false deployment signal, thereby causing airbag 28 to deploy when there is no collision. Such a false deployment would pose a totally unnecessary risk of injury or death due to the deployment itself, as well as an additional unnecessary risk of injury or death due to a possible loss of control of motor vehicle 22 by the driver.
What is needed, therefore, is a reliable and simple airbag deployment-control system that does not require replacement or extensive modification of the original (factory-installed) airbag deployment system of motor vehicle 22.